In the motor vehicle industry, endeavors are continually being made to reduce the vehicle weight in favor of fuel economy. Since usually not inconsiderable quantities of electrical conductors as well as cable harnesses composed of electrical conductors are laid in motor vehicles, the motor vehicle industry is also endeavoring to reduce the weight of cable harnesses, on account of which the copper cross-sections of the conductors are reduced to values of between approximately 0.13 mm2 and approximately 0.08 mm2, so that the diameter at the outer surface of the insulation of these electrical conductors with a reduced cross-sectional area is only approximately 0.8 mm.
However, this proves to be a problem insofar as electrical conductors of this kind with a reduced outside diameter can no longer be sheathed in the traditional manner with an elastic sealing element which during its manufacture by injection moulding has already been made with a through-opening for receiving an electrical conductor. Thus with an inside diameter of approximately 0.65 to 0.8 mm the manufacturing limit of such through-openings passing through a sealing element is reached, as a result of which the contraction or compression force which is applied by the sealing element to an electrical conductor introduced into its through-opening is not always sufficient to ensure adequately tight sealing.